# hodoku
[
](https://github.com/udoprog/hodoku)
[
](https://crates.io/crates/hodoku)
[
](https://docs.rs/hodoku)
[
](https://github.com/udoprog/hodoku/actions?query=branch%3Amain)
A simple set of macros to aid testing with try operations.
This crate allows for easily writing functions and expression where `?` is
automatically translated into `.unwrap()`.
It is syntactically desirable to use `?`. This however causes issues during
testing, because a failing test lacks a stack trace which helps you track
down the exact line that errored.
```rust
#[test]
fn test_case() -> Result<(), &'static str> {
let value = function()?;
assert_eq!(value, 42);
Ok(())
}
```
By default you'd get this when `function()?` errors:
```text
---- test_case stdout ----
Error: "bad"
thread 'test_case' panicked at 'assertion failed: `(left == right)`
left: `1`,
right: `0`: the test returned a termination value with a non-zero status code (1) which indicates a failure', \library\test\src\lib.rs:185:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
test_case
```
Note how there's no information on which line the test failed on.
But with the inclusion of `#[hodoku::function]` you get this:
```rust
#[test]
#[hodoku::function]
fn test_case() -> Result<(), &'static str> {
let value = function()?;
assert_eq!(value, 42);
Ok(())
}
```
```text
---- test_case stdout ----
thread 'test_case' panicked at 'called `Result::unwrap()` on an `Err` value: "bad"', tests\failing.rs:8:27
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
test_case
```
This is exactly why we want to make use of `.unwrap()` instead of the try
operator tests. It indicates the exact line that errored.
## Examples
Use of `#[hodoku::function]`.
```rust
#[hodoku::function]
fn hello() {
let value = Some(42)?;
assert_eq!(value, 42);
}
hello();
```
Unwrapping expressions:
```rust
let value = hodoku::expr!(Some(42)?);
assert_eq!(value, 42);
```